Minify CSS
CSSStrips whitespace and comments, then rewrites CSS to the smallest equivalent form.
Filter
rewrite_css
· Filter docs
A mod_pagespeed 1.1 filter. ModPageSpeed 2.0 applies it as part of one always-on pipeline, not as a separate switch.
Original
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Optimized
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Both frames render identically — that's the goal. The win is in the bytes and requests
below, not the look. They're served live by mod_pagespeed 1.1 on
demo-httpd-1.1.modpagespeed.com; the optimized frame
applies only this filter. Right after a cache purge it may briefly match the original while
the worker rewrites it — reload to see the result.
Measured impact
Total bytes
721 B 588 B
−18% HTML size
685 B 558 B
−19% What changed in the source
The page's HTML, before and after this filter. Red lines are removed, green lines are added.
<html>
<head>
<title>rewrite_css example</title>
- <style type='text/css'>
- #iddy, #anotherId {
- /* This comment will be stripped.*/
- border: solid 1px #cccccc;
- padding: 1.2em;
- float: left;
- color:WindowText;
- }
- div.classy span, div.classy img {
- display: block;
- border: none !important;
- background: none !important;
- }
- </style>
- <link rel="stylesheet" type="text/css" href="styles/yellow.css">
+ <style type='text/css'>#iddy,#anotherId{border:solid 1px #ccc;padding:1.2em;float:left;color:WindowText}div.classy span,div.classy img{display:block;border:none!important;background:none!important}</style>
+ <link rel="stylesheet" type="text/css" href="styles/A.yellow.css.pagespeed.cf.KM5K8SbHQL.css">
</head>
<body>
<div class="blue yellow big bold">